Power transmission mechanism



June 14, 1932. V p M sALERNl 1,863,110

POWER TRANSMISSION MECHANISM Filed Oct. 8, 1930 12 heetseet l w W a 66/9/9 1 624 i 2? June 1932- P. M. SALERNI POWER TRANSMISSION MECHANISM Filed Oct. 8, 1950 12 Sheets-Sheet 2 June 14, v sAL Nl POWER TRANSMISS ION MECHANISM Filed Oct. 8, 1930 .$heets-Sheet 3 June 14, 1932. R M SALERNI 1,863,110

POWER TRANSMI S S ION MECHANI SM Filed Oct. 8, 1930 12 hee s-Sheet 4 MI 9% MW MW abhwwqw June 14, 1932. SALERN! Filed Oct. 8, 1930 12 Sheets-Sheet 5 June 14, 1932.

P. M. SALERNI POWER TRANSMISSION MECHANISM Filed Oct. 8, 1950 12 Sheets-Sheet 6 June P. M. SALERNI POWER TRANSMISSION MECHANISM Filed Oct. 8, 1950 12 Sheets-Sheet 7 June 14, 1932.

P. M. SALERNI Q 1,863,110

POWER TRANSMISS ION MECHANISM Filed Oct. 8, 1950 12 Sheets-Sheet 8 June14, 1932. v R 1,863,110

POWER TRANSMIS S ION MECHANISM Filed Oct. 8, 1950 12 Sheets-Sheet 9 z a FZIWT'TF' g T. L a W J 1932- P. M. SALERNI PQWER TRANSMISSION MECHANISM Filed Oct. 8, 1930 12.5heetS-She9b l0 ulllldrlllf'lnl" 'IIIIIIIIII "III-II June 14, 1932. p SALERNl 1,863,110

POWER TRANSMISSION MECHANISM Filed Oct. 8, 1930 12 Shets-Sheet ll 15 12 6 ii i fia J Fz jll i l June 14, P AL 1,863,1 POWER TRANSMISSION MECHANISM Filed Oct. 8, 1950 12 Sheets-Sheet 12 W %*a 24768 74 2a /17 Patented June 14, 1932 UNITED ,sr 'rss RATENT OFFICE POWER TRANSMISSION MECHANISM Application filed October 8, 1930, Serial No. 487,187, and in Great Britain October 16, 1929.

This invention relates to power transmission mechanism and has reference to epicyclic or differential gearing comprising an axially movable or slidable clutch member (or members) 'by means of which a shaft, usually the driven shaft, can be connected and made to rotate with one or more members of the gearing.

Accordin to the present invention I ro-' vide in gearlng of the kind above referre to, means whereby the connection of the said clutch member'with the desired member or members of the gearing can be effected only when the parts to be connected are rotating at the same or substantially the same speed. For this purpose I provide balking or synchronizingmechanism between the parts to be connected, and this mechanism may comprise a balking ring having seatings or stops that can be engaged by dogs, pro]ections or. seatings on the clutch member, the said balking ring being frictionally. controlled in such manner that when the speeds of the rotating parts to be coupled are equal or substantially equal, it is displaced to allow the members to engage to provide the driving connection which is preferably effected by means of dogs, teeth or theli e on the clutch member engaging with dogs, teeth or the like on the other member, so as to provide a positive bidirectional drive throu h material under shear load; The said ba g ring may be in frictional engagement or contact with a rotatingmember or gear wheel of the epic clic gearing, and it is maintained in the position in which its seatings or sto s prevent the dogs or the like on the slidab e clutch member from engaging with the dogs or the like on the'rotating member or gear wheel of the gearing by the frictional contact with the said rotatmg member or gear wheel, which latter, when its speed tends to equal that of the slidable clutch member, displaces the said ring to enable the dogs on the slidable clutch member to engage with those on the gear wheel and thus establish the drive. The oalking mechanism hereinbefore referred to is generally employed in cases where it is necessary for the speed of the rotating memoer or gear wheel of the gearing to be reduced, so that when it tends to be less than that of the slidable clutch member which is splined on the driven shaft, frictional drag is exerted on the balking ring for the purpose of displacing the latter and allowing the dogs on the two rotating members to interrengage when the latter attain rotational synchronism. The balking ring may be provided with openings or gaps or may otherwise be formed so as to receive the dogs or projections that engage with the seatings or stops on the balking ring, and preferably a seating or stop is provided oneach side of each opening so that a dog or projection can engage with either seating. The balking ring may be rotatably connected with the driven shaft or the slidable clutch member in such manner that the said ring can be rotationally displaced relatively to the driven shaft or the slidable clutch member for the purpose of 7 permitting of engagement of the required. members. The slldable clutch member may be moved into the engaging position by hand or by means of a spring, or the construction may be such that the clutch member is moved 7 by hand, while the parts to be connected are rotating at different speeds, into the position where it encounters the projections or seatings on the balkin ring, whereupon spring pressure is applie ready to effect the engagement'of the slidable clutch member with the rotatin member or gear wheel when rotational sync ronism takes lace. An operating lever for moving the slidable clutch member may comprise two parts with an inter- 5 posed spring which when the lever is actuated to slide the clutch member, is compressed ready to force this member into driving engagement with the other member when rotational synchronism is attained. The present no invention is especially applicable to the epicyclic gearing. set forth in the specifications of my co-pending English patent applications N os. 31,47 8 of 1929 23,597 of 1930, and

23,599 of 1930, and any 0 the features according to the present invention may be combined with any or all of the features covered in the said patent applications.

In order that the said invention may be clearly understood and readily carried into effect, the same will ,now be more fully 'described with reference to the accompanying drawings, in which a Figure 1 is a vertlc'al longitudinal sectional view of one construction of the difi'erential tor epicyclic gearing embodying this invention.

Figure 2 is an end View looking in the direction of the arrow X in Figure 1.

Figure 3 isa vertical sectional view showing more particularly the controlling or operating mechanism for actuating the gearing,

the outline of the latter being represented in.

dotted lines in this figure.

Figure 4 is an end view of the controllin'g or operating mechanism looking inthe direction of the arrow'Y in Figure 3.

parts of the controlling or operating mechanism shown in different positions.

v ferred to.

, ferred to.

Figure 12 is a detail view hereinafter re Figures 13 to 20 are diagrams illustrating the gearing (mainly in dotted lines) and the controllin positions in its gate. 1

Fi ures 21 to 28 are diagrammatic views of the internal synchronizing or balking mechanism. a

Figure 29 is an end view similar to Figure 4 illustrating a modification hereinafter re-.

The gearing is contained in.a casing '1 in which at one end the driving shaft 2 is suported in a ball bearing, the driven shaft 3 ing supported in a ball bearing at the other end of the casing 1. The inner or free end of the driven shaft 3 is formed with a spigot that fits within the inner end of the dnving shaft 2 as shown in Figure 1. The driving shaft 2 is formed with or has secured thereon a driving sun gear wheel 4 which is in mesh with the larger planet pinions 5 of preferably three compound planet pinions (see Fig: urea .2 6 and 7) of which the smaller pinions Gare 1n mesh with a driven sun gear wheel 7 of annular or hollow formation as shown.

' The compound planet pinions 5,6, are supported at their ends in ball bearings 5a and mounted in end plates 8 and 9 that form part of a cage or carrier, the bod 10 of which is illustrated in perspective in igure 12 the said end plates 8 and 9 in the example shown being secured to the cage. body 10 by means of'bolts 11 that extend through substantial bosses on the cage body and are scurd in or operating lever in difieren't posit-ion by-nuts so as to clamp the end plates securely to the Body 10 the whole forming the planet cage or carrier which will hereinafter be referred tro as the cage 10. The body and t e end plates are preferabl made. of duralumin. Surrounding the said cage 10 is an annulus 12-which at the rear end is formed I or provided with a plate 13, whose inner part is mounted in a ball bearing 14 supported in a diaphragm or web 10: forming part of the casing 1 the said annulus 12 being provided with internal teeth 15 with which mesh the larger planet pinions 5 of the three compound planet pinions. Y I

In the example illustrated the teeth of the difierent gear wheels and pinions are of heli-v cal formation. At or near the ends of each of the compound planet [pinions are provided rollers or circular bearing surfaces 16 and 17 the diameters of which, are e ual to the diameters'of the pitch circles of t e larger planet pinions 5, the'three rollers 16 being adapted to travel around, a roller support or' circular bearin surface 18 which is provided around the driving shaft 2 andfis of a diameter equal to the diameter of the pitch circle" of the driving sun wheel 4. Thesaid rollers 16 and 17 also contact with and travel around roller tracks or bearings 19 and 20 res ectively, provided on the internal surface 0 the aforesaid annulus 12 the diameters of the said roller tracks 19 and 20 being equal to the diameter of the pitch circle of the internal teeth 15 of the annulus. The said rollers 17 are each provided with a reduced circular portion 21 constituting another roller or bearing surface equal to the'pitch circle of its teeth and which engage respectivel with the ,rollerspr bearing surfaces 21 an 22on the three compound planet pinions so thatthe driven sun whee-l (which is of annular formation as aforesaid) is supported within. and by the said rollers or supports 21 and 22 on the equi-spaced com- .pound lanet' pinions. The'rollers or bearing sur aces 23 and 24 particularly the former are made'separat'e fromthe'driven sun wheel, 7 and the compound roller support 17 and 21 is made separate from the compound planet pinion as shown in Figpre 1,"in order to facilitate assembly of t e parts. The compound roller sup rts 17 and 21 is held against endwise 'splacement on the compound planet by a sprin'gring 21a. The internal gearing and associated parts after assemblyare finall held in osition by the end cage plate 9 whic is bolted to the cage 10 and bearings which properly support the various parts and ensure correct meshing oi the gear teeth whilst they relieve the bearings 5a and 6a of the compound planet pinions of separation loads and centrifugal loads and it is this construction that renders possible the use of the annular driven sun wheel 7 which having no hub or similar central support enables means to be provided for passing into or through it to connect or en age different parts of the gearing as hereina ter described. In the example shown the said pitch circle rollers and the like are so constructed as to serve as thrust bearings and to prevent undesirable axial or endwise displacement by co-operating with side supports or surfaces, flanges or the like at or near the pitch circle diameters onadjacent and coacting rollers or the like. For this purpose the roller support 18 and the roller track 19 are provided with flanges 18a and 19a that fit in grooves 16a in the roller 16, and the roller 23 engages with side surfaces or flanges at 23a on or adjacent to the roller 17 whilst the roller 24 engages with side surfaces or flanges at 2412 on or adjacent to the roller 22. -l[nthis manner the parts are held against axial or endwise thrust or displacement in both directions. This construction also permits of the use of helical gear wheels and pinions without the use of ordinary thrust bearings. lln assembling the rollers 16 and the compound planets 5 and 61they are placed within the track 19 and internal teeth 15 in the annulus respectively so as to lie against each other and after placing the roller supports 18 and 24 in the central position, they can be rolled around these supports into their proper positions to permit of other parts being fitted or assembled.

The inner end of the driving shaft 2, the

5 annular driven sun wheel 7, the end cage plate 9 and the annulus plate 13, are provided with internally disposed dogs or teeth 2a; 7a, 9a and 13a respectively. Splined around the said driven shaft 3 is a slidable sleeve 25 having external dogs 25a which are adapted to engage at difierent times with any one of the sets of dogs 20;, 7a, 9a and 13a by slidable movement of the sleeve in either direction, f-or'which purpose the sleeve can be slidably moved in and through the annular driven sun wheel Z. The said dogs 2512 .are preferably but not necessarily of such length that whilst they can engage with-the dogs 7a, they can when engaging with the dogs 2a also engage with the dogs M for the purpose of locking the gearing so that it will rotate bodily as hereinafter described. Balking or synchronizing means hereinafter more fully referred to are provided for the purpose of preventing the dogs 25a on the slidable sleeve 25 from engaging with the dogs 7 a on the driven sunwheel 7 or with the dogs 2a on the driven shaft 2, until such time as the .rotating members to be engaged attain rotational synchronism. On the exterior of the cage plate 8, peripheral dogs or teeth 8a are formed and similar dogs or teeth 12a are formed on the rear part of the annulus, locking means being provided for engaging with these external dogs or teeth to hold either the cage 10 or the annulus 12 against rotation as hereinafter described. The sleeve 25 is slidably moved 'for the purpose of engaging its dogs 250, with any of the sets of dogs 20., 7a,, 9a or 130, bymeans of an operating lever 26- (see Figures 3 and 4), which is mounted on a ball Joint 27 so as to be capable of movement in opposite directions in the plane of the longitudinal axis of the gearing orin different planes across the said axis. The lower part of the lever 26 is formed with a fork 28 to which is pivotally attached a slotted plate 29 that is loosely connected with the said sleeve 25 by means of collars 25b in such manner that the plate 29 can be angularly moved relatively to the collars 256 by transverse movement of the operating'lever 26, the said collars however enabling the sleeve 25 to be slidably moved when the operating lever is moved in the longitudinal direction. 0n the lower part of the said plate 29 is a slotted or bifurcated portion 30 that is slidably attached to the upper end of a wide arm or lever 31 fixed on a shaft or spindle 32 that is adapted to be rocked in hearings in the lower part of the casing 1 when the lever 31 is moved by transverse movement of the operating lever 26. Fixed on the sa1d shaft 32 are cam levers 33 and 34 which are angularly disposed as shown in Figure l. The cam lever 33 engages with a roller 35 which serves to connect the inner ends of two bell crank levers 36, 36 that are pivoted on pins 37 mounted in fixedbearings in the casing 1 the outer ends of these bell crank levers having pawls 38 (see Figures l and la) pivotally mounted thereon and co-operating therewith in such manner that the pivotal movement is resisted by the springs 39.- These pawls 38 are adapted to engage with the locking dogs 12a on the annulus 12 at diametrically opposite points and they are so connected with the bell crank levers 33 that the springs serve as shock absorbers when the pawls engage with the dogs 12a for which purpose the springs 39, in the example shown are associated with plungers 3362 that bear against curved abutments or restraining surfaces formed in the levers 36.

Any suitable construction, of resilient or shock absorbing pawls may be provided. The bell crank levers 36 are under the infiuence of springs 40 which tend to maintain the said levers in the position in which the pawls 38 are in engagement with the annulus ogs 12a. As it is necessary that thepawls 38 comprises a plate'or ring 41loosel mounted i around a coned part on or of the iaphragm or web 1a on'the gear box casing so that it is free to be maintained bythe action of gravity in frictional contact with the end face or I plate 13 of the annulus 12- for which purpose the ring 41 is provided with a-frictional surface as shown in Figures 1, 3 and 5. This ring 4'1 isalseprovided with oppositely disposed notches .42 adjacent to each vof which I 15 are two inclined stops or seatings 43 that can be engaged by inclined seatings on projec- .tions 44 on the said bell crank levers 36. The inclination of the said seatings is preferably about 6. So long as each or either projection. 44 engages with one of the. inclined stops or seatings 43 the pawls 38 are maintainedout of engagement with the'annulus dogs 12a, but upon the said balking ring 41 beingrotationally displaced for example by reason of 25. its frictional contact with the annulus plate 13,'the seatings 43 move away from the projections 44 so that thelatter are free to enter the notches 42in the plate 41 under the in- "fluence of the springs 40, which'latter therefore at the same time cause the pawls 38 to engage with the annulus dogs 12a. Although thevbalking ring 41 is frictionally displaced A as aforesaid the contact with the annulllsface or plate 13 is sufliciently anti-frictional owing to the loose mounting of the ring to avoid 'undueheating and wear by annulus.

The other .cam'

rotation of the lever 34011 the shaft 32 engages with a roller 45 that connects two bell.

crank levers-46 pivoted at 47 similxar to the 'bell crank'levers 36 and carrying awls 48 "that are adapted to engage with th locking dogs Be on the cage plate 8 the said pawls 48 'co-operating with shock absorbing springs'49 in a similar manner to that described in connection with the pawls 38. Similar balking or; synchronizing means are-' provided for preventing engagement of the locking pawls 48 with the cage'dogs 8a, except at the. proper 50 time, these means comprising a balking ring 51 (see Figures 1, 3 and 5) havingnotches be displaced by its contact with the face ofv the cage plate 8. The angular disposition of the aforesaid cam. levers 33 and 34 is such that angular movement of theshaft 32 caused by transversely moving the operating lever 26 will according tothe direction of movement, cause either one or other of the said cam levers to move and'operate the mechanism for withdrawing the respective locking pawls from engagement with the annulus dogs or the cage dogs, whilst subsequent movement in the same direction will displace the other cam lever and allow its respective pawls to be moved under the influence of the springs associated therewith tawards eng ment with the corresponding dogs on the an-. nulus or cage, the engagement ofeither set 5f pawls 38 or 48 being permitted only when the balking ring 41 or 51 associated therewith is displaced as hereinbefore, described. In order that either of the balking rings 41 or 51 can be displaced'at will to release the locking pawls so that the latter. can-engage with their respective dogs, the cam levers 33 and 34 have. associated therewith projections 33a and 34a respectively which are adapted to co-operate with lugs 41a and 51a on the balking rings when required. The projections 33a and 34a are adapted to engage with the said lugs 41a andlilja by imparting movement to the operating lever 26 beyond-the normal amount required for gear changing, and when the operating lever is so moved, the said pro jections engage with the lugs for displacing the particular balking ring concerned, thus on the saidlever and provided with an arm 58 that can engage with the said plate 56. The operating lever is movable in a. gate 60 having a medial orlongitudinal slot 61 and lateral slots 62, 63., 64 and 65 disposed as shown in Figures 13 to 20 one end of the medial s ot 6'1 extending beyond the slots 64 and 65 soas to form a notch'66 into which the operating lever can be moved and retained as hereinafter described. Longitudinal movement of the operating lever in either direction in the medial slot imparts sliding movement to the aforesaid sleeve 25 having the dogs 25a that can engage with the sets of dogs 2a, 7a, 9a and 13a. Transverse movement of the operating lever into the lateral.

slots on one side of the medial slot will oper- 1 ate themechanism that enables the .pawls say 38 to engage with the annulus dogs 12a whilst transverse movement of the operating lever in-the other direction will operate the mechanism that enables the locking pawls 48 to enga 'e with the cage dogs 8a as hereinafter described." The said "catch 55 on the operating lever forms a stop for engaging with the ends 1 of the lateral slots so as to hmit the move- 7 ment of the operating lever when this isactuated for the diiierent forward speeds. By lifting'the said plate 56 against the action 1 lugs 4111 or 51a so as to displace either of the balking rings 41 or 51.. The said catch 55 also engages with projections 60a on the gate 60 for holding the operating lever 26 in neutral, whilst it can also engage with a catch.

66a associated with a notch 66 when the operating lever is moved to engage top gear as hereinafter more fully described.

Figure 13 illustrates the gearingand the operating lever 26 in the position-they occupy when the gearing is set for reverse. In order to place the gearing in this position, the operating lever 26 is moved in the gate 60 to the end of the slot 61 opposite to the slot 62, this movement resulting in the sleeve 25 being axially or-slidably displaced so that its dogs 25a are brought into engag me t with the dogs 134; on the annulus 12. T e operating lever 26 is then moved into the slot 62, this movement causing the aforesaid lever 31 to be operatedin a direction which displaces the cam lever 34 to allow the spring 50 to actuate or tend to actuate the associated mechanism for causing the locking pawls 48 to engage with the dogs 8a on the cage plate 8 the other locking pawls 38 pertaining to the annulus external dogs 12a being maintained out of engagement so that the annulus is free to rotate. Figure 13 shows the dogs 25a and 13a engaged and thepawls 48- engagiing with the cage dogs 8a, whilst the loc ing pawls 38a are shown out of engagement with the annulus external dogs 12a. When the parts are in thexpositions shown in thisfigure, the driving shaft 2 imparts rotation tothe planet pinions 5 through the driving sun wheel 4 fixed on the said shaft 2 and as the planet pinions are held a ainst rotation about the axis of the gearing y the looking pawls 48 engaging with the external cage dogs 8a on the cage 10 they revolve on their own axes. The larger planet pinions 5 which mesh with the internal teeth? 15.0f the annulus 12 therefore drive the annulus 12 in a direction opposite to the direction of rotation of the driving shaft and the sun wheel 4 fixed thereon, so that owing to'the dogs a on the sleeve 25 which is splined on the driven shaft, being inengagement with the dogs 13a on the rotating annulus, the driven shaft 3 is. rotated to provide the reverse drive. When moving the operati'nglever 26 into the slot 62 for reverse, the balking ring 51 is usually in a position to prevent the locking pawls 48 from engaging with the external dogs 8a on the cage plate 8. The operating lever can therefore be moved to an extent required to enable one of the, projections 34a on the cam lever 34 to engage with the appropriate lugs 51a on the balking ring 51 which is thereby displaced to allow the retaining projections 54 to move into the slots 52 (see Figure 11) and thus permit the pawls 48 to engage with the external dogs 8a on the cage plate 8 owing to the springs acting on the bell crank levers 46.

In order 'to engage first or emergency low gear, the operating lever 26 is moved out of the slot 62 into the slot 61, which movement resultsin the cam lever 34 actuating the aforesaid mechanism for withdrawing the pawls 48 out of engagement with the dogs 8a on the cage whilst the other pawls 38 remain out of engagement with the dogs 120; on the annulus 12. Movement of the operating lever along the slot 61 towards the lateral slot 63 to the position shown in Figure 14 .(which is a neutral position) results'in the dogs 25a on the sleeve 25 being withdrawn from the internal dogs 13a on the annulus.

The lever 26 is moved from the neutral tion alonthe slot 61 to the slot'63 which sults in t e dogs 25a on the slidable sleeve 25 engaging with the internal dogs 9a on the cage plate 9 whilst the lateral movement of the lever 26 into the slotv 63 causes the lever 31 and the shaft 32 to be rocked to displace the cam lever 3.3,"which thereforereleases the bell crank levers 36 so that they are moved by,

the springs 40 to cause the locking pawls 38 to engage with the annulus external dogs 12a and thus lock the annulus a ainst rotation the other locking pawls 48 being maintained out of engagement with the dogs 8a on the cage. In this-position of the parts which is shown in Fi from the driving shaft 2 and the fixed sun re 15 the drive is transmitted v wheel 4 to the lanet pinions 5, which, owing to the annulus eing held a ainst rotation b the locking pawls 38, revo ve together wit the free cage 10 around the axis of the earing at ,a 5 ed less than that of vthe driving shaft, so t at the revolving cage which engages by means of. its do 9a with the dogs 25a on the sleeve 25 splined' to the driven shaft, drives the driven shaft at the reduced speed which represents first gear or emergency low speed. If the balking plate or rin 41 should be in a position toprevent the 100 'ng pawls 38 from engaging with the dogs 12a for instance in starting from rest,

the displacing projections 33a on the cam le-. ver 33 are caused to engage with the lug 41a on the 'balk'in plate by imparting extra movement tot e operating lever 26 in the slot 63 after raising the catch 55'thus displacing the'ring and allowing the locking pawls 38 to be moved into engagement with the annulus dogs 12a by the springs 40.

Movement of the operating lever 26 out of the slot 63 results in the locking pawls38 being disengaged from the external dogs 12a dogs 25a are withdrawn with the internal cage dogs 9a. For the puron the annulus, and movement of the operating lever along the slot 61 to the neutral position shown in Figure 16 causes the sliding sleeve 25. to be axially displaced so that its rom engagement pose of engaging second or ordinary low gear the operating lever 26 is moved along the middle slot '61 towards the slot 64 so as to slide the sleeve 25 in the direction for enabling its dogs 25a to engage with the internal dogs 7a on the driven sun wheel 7. Engagement of the said dogs25a and 7a is however prevented by means ofa balking or synchronizing ring 67 (see Fi res 1 and 21 to 24) until such time as the driven sun wheel 7' and the driven shaft 3 with the sleeve 25 Y are rotating at the samespeed; The balking result that the balking .rin

rotated by the sun wheel 7 yreason of the ,on the slidable sleeve 25 to obstruct the latter and prevent them from engaging with the dogs 7a on the sun wheel 7. A support ring having internal projections 71 that fit in splines 72 on the sleeve 25, is connectedv with the said balking ring 67 so as to be capable of rotating the latter, by means of a projec- "tion 73 on the balking ring engaging with a slot 74 in the support ring of' such size that a limited rotational displacement of the balking ring can take place relatively to the support ring. At the time that the dogs 25a on the slidable sleeve 25 are about to engage" with thev dogs 7a on the driven sun wheel 7, the latter is rotating faster than the said sleeve 25 and the driven member 3 with the 67 tends to be frictional contact with the washer 68, and its projections 69 aretherefore held in the osition shown in the! developed plan view in Figure 22 to prevent engagement of the dogs 25a with thedo s 70 on the sun wheel the speed of'the driving shaft 2, the rota- 7, By decelerating t e engine and reducing tional speed of the sun wheel 7 will be decreased and when it tends to be less than that L of the driven shaft. 3, a frictional drag is exerted on the balking ring 67 by means of the washer 68, thus displacing the saidbalking ring 67 relatively to the support ring 7 0 owing to the lost motion between the projection 73 and the elongated slot.74, with the result that the balkingring projections 69 are moved out of the path of the dogs 25a,

- which can therefore be slid into engagement with the dogs 7a on the sun-wheel 7 as shown in Figures 23 and 24 the said projections 69 splines in the slidable sleeve 25 sothat the balking ring 67 is maintained in a definite position in which it is held against relative or unrequired rotational displacement. during other operations of the gearing. The operating lever 26 can now be moved into the slot 64, (see Figure 17) to free or release the mechanism that, tends to engage the locking pawls 48 with the external dogs So on the 'cage. At the time that the sun wheel 7 attains the same speed as that of the driven member 3, the planet cage 10 which had been rotating in a forward direction for first gear is decelerating and by the time that the operating lever 26 has been moved into the slot 64, the cage 1() has commenced to rotate in the reverse direction. This reverse rotation of the cage 10 maintains the synchronizer or balking plate or ring 51, which is in frictional contact with the cage plate 8 in a position in which its inclined seatings 53 are engaged by the seatings on the projections 54 of the bell crank levers 46 to prevent the lockingv pawls 48 from engaging with the external dogs 8a on the cage as shownin Figures 8 and 10. Upon accelerating the engine in the ordinary way, the cage will decelerate again and'at'the moment it stops and tends to reverse its direction of rotation, it will frictionally displacethe synchronizer or balking plate or ring 51 so as to cause the seatings 53 thereon to be moved out of engagement withthe balking projections 54 (see Figure 11) with the result that the pawls 48 are caused to engage with the external dogs 81; on the cage (see Figure 9) un-. der the influence of the springs 50 at orvabout the moment that the cage is stationary. The parts are now in the position shown in. Figure 17, and the drive is transmitted from the driving shaft 2 and the driving sun wheel 4 to the planet pinions 5 and 6, which, owing to the planet cage 10 being held against rotation by the locking pawls 48, revolve on their own axes the annulus bein free at this time so that the smaller pla' et pinions 6 which are in meshwith the driven sun wheel 7 drive the latter at a eedless than that of the driving shaft, t is reduced s d (which represents second gear or me ium low speed) being imparted to the driven shaft 3 through the engaging sun wheel dogs 7a and the dogs 250; on the slidable sleeve 25 which is splined to the driven shaft. By moving the operating lever 26 outof the slot 64 into the slot 61, as shown in Figure 18, the'locking pawls 48 are'disengaged from the external dogs 8a on the cage and the gearing is therefore in a neutral position and although the sleeve 'dogs 25a remain engaged with the sun wheel dogs 7a because the slidable sleeve 25 has not been axially moved, the gearing merely rotates idly in this position.

passing between the dogs 25a and fitting in In changing from second gear to third gear, the operating lever 26-is moved out of' the slot 64 across the slot 61 and into the slot 65. The firstvpa'rt of this movement results in the mechanism being operated for withdrawing the locking pawls 48 from engagement with the cage dogs 8a as aforesaid in connection with Figure 18 whilst the latter part of the movement, i. e. from the position shown in Figure-18 into the slot 64 as shown in Figure 19 frees or releases the mechanism that tends to engage the locking pawls 38 with the external dogs 12a on the annulus v12. Actual engagement of the locking pawls 38 with thel nnulus-dogs- 12a is however prevented until theengine has decelerated to an extent which tends to reverse thedirection of rotation of the annulus. At the moment the annulus stops and tends torotate in the reverse direction, it displaces the balking plate or ring 41 by frictional contact therewith so that the seatings 43 on the said ring 41 move away from the balking projections 44 on the hell crank levers 36 thus releasing the locking pawls 38 and permitting them to engage with the external dogs 12a on the annulus under the influence of the springs 40 at or about the moment the annulus is stationary. The slidahle sleeve is not axially displaced in changing from the second gear to third gear, so that the dogs 25a on this sleeve remain in engagement with the internal dogs 7 a on the sun wheel 7. The various parts are now in the position illustrated in Figure 19 and the a drive is transmitted from the driving shaft 2 through the sun wheel 4 so as to rotate the planet cage 10 and the planet pinions about the axis of the gearing, the planet pinions revolving about their own axes owing to the larger pinions 5 revolving in meshwith the internal teeth 15 of the annulus 12 which is now locked by the pawls 38 so thattthe sun wheel 7 is driven by the smaller planet pinions 6 at a speed less than that of the driv; ing shaft 2 this speed which is higher than that imparted when the parts are in the position shown in Figure 17' and which represents third gear or high speed being imparted to the driven shaft 3 through the engaging sun wheel dogs 7 a and thedogs 25a on the sleeve 25 splined on the driven shaft.

When it is'desired to change from third gear to second gear the operating lever 26 is merely moved out of the slot into the slot 64 and the engine accelerated in the usual way.

in changing from third gear to top gear the operating lever 26 is moved out of the slot 65 and into the slot 66. The initial or lateral movement of the lever 26 into the v medial slot 61 as shown in Figure 18 causes the mechanism to be operated for moving the and into the slot or notch 66, which is an extension of the medial slot 61, tends to move the slidable sleeve 25 so that its dogs 25a will engage with the dogs 2a on the driving shaft 2. The engagement of the dogs 25a and 2a is however prevented while the driving shaft 2 and the driven shaft 3 are rotating at different speeds by means of a balking or synchronizing ring 76 (see Figures 1 and 25"to 28) which isprovided with projections 77 having 6 inclined faces or seatings that are adapted to be engaged by similar inclined faces or seatings on projections 78 formed at the end of the sleeve 25. At the time that the sleeve dogs 25a are moved towards engagement with the dogs 2a, the driving shaft 2 is rotating faster than the driven shaft 3 so that frictional contact between an antifrictional washer 79 carried by the driving shaft and the eoned surface of the balking ring 76 will maintain this ring in the osition shown intFigures 25 and 26, in whic its projections 77 are engaged by the projections 78 on the sleeve 25 thus holding the sleeve dogs 25a out of engagement'with the dogs 2a on the driving shaft 2 this position being shown more clearly in the developed plan view in Figure 26. Upon decelerating the engine, the speed of the driving shaft will equal and tend to fall below that of the driven shaft '3 and the slidable sleeve 25 thereon, thus causing a frictional drag on the said balking ring 76 which is therefore displaced to move the seatings on its projections 77 away from the seatings on the sleeve projections 78 which latter can now move into recesses 80 in the balking ring 76 (see Figures 27 and 28) with the result that the sleeve 25 in moving forward causes its dogs 25a to engage synchronously with the dogs 2a thus directly connecting'the driving shaft 2 with the driven shaft. to provide top speed. In this position of the parts, which is shown in Figure 20, the two sets of locking pawls 36 and 48 are maintained in the unlocked positious, leaving the cage and the annulus free. As shown/in this figure, the dogs 25a on the slidable sleeve 25, in addition to engaging with the dogs 2a, are also in engagement with the dogs'7a on the sun wheel 7, but owing to the annulus and the cage being free this engagement of the dogs 25a and 7a merely results in the gearing rotating bodily about the axes of the driving and driven shafts. In order to avoid the necessity of maintaining hand pressure on the operating lever26 after heing moved into the slot 66 for top gear until such time as the driving member 2 and the driven member 3 are rotating at the same speed the said lever is constituted by two parts that are pivotally connected with an interposed spring 59 (see Figure 3) and when the-lever is placed in the slot 66 it is locked therein by means of the catch 55 engaging a stop 66a on the gate 60 so that whilst the operating lever is maintained in this position, the spring 59 is compressed, thus act: ing on the lower partof the lever and tending to move it and the'sleeve 25 in the direction for engaging the sleeve dogs 25a'with the driving dogs 211 when speed synchronization takes place as aforesaid. To move the.

operating lever 26 out of the top gear slot or notch 66 it is pulled or pushed by gripping the knob 57 which being pivotally mounted on the lever 26 is displaced'to raise the arm 58 and thus lift the plate 56, thereby releasing the catch 55 from engagement with the stop 66a. This catch 55 can engage with .either of the twotransverse stops 60a on the v 14 or Figure 16. 1

gate 60 to hold the operating lever 26 in either of the two neutral positions shownin. Figure In changing from second-gear to top gear, the operation is similar to that described for changing from third gear to top gear. In changing from top gear to second gear or to third gear, the operating lever is moved from the slot or notch 66 into theslot 65 for third gear, or into the slot 64 for second gear, and the engine is accelerated as required.

Itwill be observed that in connection with the internal balking 'or synchronizing means comprising the rings 67 and 76 aswell as'in connection with the external balking or synchronizing means comprising the balking rings 41 and 51, a pair of inclined stops or seatings is associated with each of the openings or-recesses into which the balking projection can enter when rotational orstatic synchronization takes place," the seatings associated with each openingbeing arranged one on each side of the, latter, so that the balking projection can engage with either one or the oth- 'er. If during gear changing the point of rotational synchronism in connection with the internalbalking means or static synchronism in connection with the external balking means should be allowed to pass so that a balking projection does not engage with the seating on one side of the opening or recess, the projection will however engage with the second seating on the other side of the opening-or" recess to prevent engagement or locking of the parts to be connected, and synchronism ,can be brought about again by acceleration or deceleration of the engine ac-' cording to requirements for enabling the driving dogs or looking Ineansto engage as hereinbefore described.

vIn the example of the gearing illustrated, the provision of the external dogs Be on the planet cage member and also the external dogs 12a on the annulus memberfenable a:

ters Patent of the United States is ing means for engaging-the said dogs operating at the time static synchronization takes.

"place, the locking of'the said members can be effected without shock, the resilient pawls .which shows a construction comprising operating, mechanism generally similar to that illustrated in Figure 4, but the bell crank levers 36 which carrythe balking projections 44 have associated therewith short levers 82 that are connected at 83 to the free ends of longer levers 84 pivotally mounted at 85'to a-fixed vers 84 ave pivotally attached thereto brak ing-shoes 86 which are adapted to engage. with a suitable external surface on the annulus in the one case, whilst similar mechanism is provided for enabling brake shoes to part of the casing. These longer leengage with a suitable external surface on the planet cage. By means of the construction illustrated'in Figure 29, the leverage provided by the short levers 82 and the longer 1evers 84 .is such as to cause the brake shoes to be forced with sufiicient pressure against the annulus (or the cage) under the influence of the springs 40 for example to hold the annulus (or the cage) against rotation. This construction' has the advantage that the frictional'engagement is effected at the time that the annulus (or the cage) is stationary, so that difliculties such as are encountered when frictional surfaces engage with rotating parts are avoided. Instead of providin a balking member inthe form of a plate or rlng such as 41 or 51 as hereinbefore referred to, I may provide a balkingmember in the form of a 'nd of shoe which can engage with the pe ripheral or other partof the annulus or the cage under the influence of spring or other pressure, the said member having inclined faces or other stops that can be engaged by 9.

said pawl or dog out of engagement with the dogs on the annulus or the cage until such time as the annulus or the cage comes to. a

tandstill as hereinbefore described. An embodiment' of this kind may also be applied to the frictional gripping or locking means described in connection with Figure 29. What I claim and desire to secureby Letpawl or pivoted dog member in such man- 'ner that the balking member maintains the 

